High-speed communication channels, such as for example electrical transmission lines across equipment backplanes of electronic equipment, are often a scarce resource. Furthermore, the associated equipment, such as connector pins or printed circuit board (PCB) transmission lines, are often a limited and expensive part of a communication system.
In a typical communication system, dedicated transmission lines are often provided for each circuit in the communication system, even if it is anticipated that the transmission lines will not be used continuously, because switching the connections of high-speed circuits to share the same transmission line is generally technically difficult and expensive. Also, sharing the same transmission line may severely degrade the high-frequency capability of the transmission line, especially if the circuits that share the transmission line employ different technology standards (e.g., communication or interface standards).
However, if different electrical circuits were able to share the same transmission line (e.g., backplane transmission line), greater efficiencies may be achieved along with possibly increased equipment capacity and/or reduced costs. As a result, there is a need for improved techniques for sharing communication channels.